Veterans Affairs Secretary David Shulkin's chief of staff falsified an email so that the secretary's wife could accompany him and his staff to Europe last year at taxpayer expense, according to an internal watchdog's investigation released Wednesday.

According to the report by the V.A.'s Office of Inspector General (OIG), Vivieca Wright Simpson, the chief of staff, altered a subordinate's email to misrepresent the purpose of the 11-day trip so that Shulkin's wife, Merle Bari, could be reimbursed by the government.

The report also said Shulkin improperly accepted tickets to Wimbledon, and questioned his decision to direct agency staff members on official time to arrange his personal sightseeing activities during the July trip to England and Denmark.

The OIG, which is responsible for internal oversight of the agency, said it launched the investigation after receiving an anonymous tip alleging that the trip was a misuse of V.A. funds. Its findings make Shulkin the latest top Trump administration official to come under fire for costly, taxpayer-funded travel.

According to the report, Simpson told staff to contact V.A. ethics officials in charge of approving travel to designate the secretary's wife as an “invitational traveler," which would have allowed her to be reimbursed by the V.A. for her $4,000 airfare.

A calendar produced by the VA Inspector General showing a summary of the planned official business and leisure time for the VA secretary's European trip.Veteran Affairs Inspector General

The ethics officials initially declined to approve the request because it did not show "sufficient government interest." That's when Simpson forwarded an email she doctored to Tammy Kennedy, the designated ethics official, that asserted the secretary was receiving an award on the trip, therefore justifying his wife's presence. The request was then approved.

The V.A. delegation for the Europe trip included Simpson, Bari, a V.A. official who has since left the agency, and aide James Gough. Six members of the secretary’s security detail also went along. The estimated total cost came to $122,334.

Shulkin has repeatedly denied wrongdoing, telling OIG investigators that he found the trip substantively valuable to V.A.’s mission. A department spokesman told The Associated Press on Wednesday that Shulkin "travels far less than any recent V.A. secretary" and does not take private jets.

Additionally, Shulkin's lawyers called the OIG report "one-sided" and said that the allegation that Shulkin had improperly accepted the Wimbledon tickets was "highly flawed, both factually and legally."

"Secretary Shulkin did nothing wrong in traveling to Europe to meet with, and learn from, America’s allies," his lawyers wrote in a letter included in the OIG's report.

Shulkin responded to the report's findings in his own letter to the inspector general, accusing the office of having an "agenda."

"Your staff's conduct related to this investigation reeks of an agenda," he wrote. "Your portrayal of this trip is overall and entirely inaccurate."

Investigators said there was no evidence that Shulkin was aware of Simpson’s "false representations," including that she had altered the email. But the report did say that it had found "serious derelictions." Investigators said the secretary used Gough, a V.A. subordinate, "as a personal travel concierge" to him and his wife.

Only three-and-a-half days of the 11-day trip were used for official business, the report said. Through interviews and documents, investigators found that the secretary and his wife took a boat tour of Copenhagen and toured two palaces and two castles while in Denmark. They also made an unplanned trip across the border to Sweden for dinner.

In London, the couple visited Buckingham Palace and Westminster Abbey, took a cruise, visited St. Paul’s Cathedral and Windsor Castle, among other places.

The inspector general recommended that Shulkin reimburse the V.A. for his wife's airfare and pay back the person who gave him the Wimbledon tickets — and Eric Nitz, an attorney for Shulkin, told NBC News Wednesday evening that the secretary has written a check to the U.S. Treasury as payment for his wife's travel.

Investigators also called on the V.A. to take "any appropriate administrative action" against Simpson and other staff.

The report said it had referred Simpson's case to the Department of Justice because altering official records might violate federal criminal law, but the Justice Department decided not to prosecute at this time.